docs: update MKFA to MFA

[Bin-fluence]

Updated from this:

Account Recovery**: Recover access using "Forgot Password" flows, Security
Codes (in case of MKFA device loss), and others.

to this:

Account Recovery**: Recover access using "Forgot Password" flows, Security
Codes (in case of MFA device loss), and others.

Related issue

Proposed changes

Checklist

• I have read the contributing guidelines.
• I have read the security policy.
• I confirm that this pull request does not address a security
  vulnerability. If this pull request addresses a security. vulnerability, I
  confirm that I got green light (please contact
  [email protected]) from the maintainers to push
  the changes.
• I have added tests that prove my fix is effective or that my feature
  works.
• I have added or changed the documentation.

Further comments

[CLAassistant]

All committers have signed the CLA.